Amid an escalating conflict between Hamas and Palestinian Authority (PA) President Mahmoud Abbas, rumours are flying that exiled Fatah leader Mohammed Dahlan is set to make a comeback.

Once considered persona non grata by Hamas, the Abu Dhabi-based power broker has for years been rumoured to be plotting his return.

But analysts say a series of secretive meetings between Hamas officials and Egyptian authorities in Cairo, coupled with the Gaza Strip's growing isolation and Abbas' increasing unpopularity, could now prove the rumours true.

Speculation peaked last month following Egypt's decision to send one million litres of fuel into Gaza after Israel, at the request of the PA, further reduced its supply of electricity to the besieged territory by at least 40 percent.

The fuel arrived just in time for the Eid al-Fitr holiday that ends the Muslim holy month of Ramadan, and provided temporary relief for an energy crisis in the coastal enclave that put Gaza on the brink of "total collapse", according to the United Nations.

The shipments, brought in through Gaza's Rafah crossing with Egypt, reportedly came at the initiative of Dahlan, a sworn enemy of Abbas, who pushed the deal through with help from the United Arab Emirates, his home in exile.

"Gaza is in desperate need of basic humanitarian aid. That is the gate through which Dahlan will return to Gaza," Nagy Shurab, a Gaza-based political analyst, told Al Jazeera.

"Egypt, in turn, is interested in restoring stability to the Sinai," he said, referring to the Sinai Peninsula bordering Gaza and Israel, where Egyptian forces are battling hardline fighters, some of whom Cairo has accused Hamas of sheltering.

By allowing Dahlan to return and take control of the security efforts at Rafah, Cairo would have a partner it trusts.

"Hamas is facing a multidimensional set of problems, but it is pragmatic enough to make a deal, even with a man it considers an enemy - as long as Dahlan can open Rafah and new doors of aid from the UAE," Shurab added.

Days after the initial fuel shipments, an unconfirmed plan leaked to the Bethlehem-based Maan News Agency highlighted what many across Gaza and the region have whispered about for months.

The document provides details of an alleged agreement between Hamas' second-in-command, Yahya Sinwar, and Dahlan. Under the deal, allegedly made during Egyptian-led talks last month, Dahlan would return to Gaza to lead the government and Hamas would run the territory's interior ministry.

Many believe that Dahlan brokered talks in Cairo between Hamas and senior Egyptian officials in an attempt to strengthen relations between Hamas and Cairo and pave the way for his return.

Living in self-imposed exile in Abu Dhabi since Abbas expelled him from Fatah in May 2011 over corruption allegations, Dahlan has cultivated a close relationship with the Emirati elite - he serves as an adviser to UAE Crown Prince Mohammed bin Zayed - and has strong ties with Egyptian President Abdel Fatah el-Sisi.

A native of Gaza's Khan Younis refugee camp, Dahlan served as Gaza's first security chief under former Palestinian leader Yasser Arafat in the 1990s. His notoriously brutal rule, including alleged torture of Hamas and Islamic Jihad activists, led some at the time to dub Gaza "Dahlanistan".

While in charge of Gaza's security forces, Dahlan dealt regularly with US and Israeli intelligence officials. After Hamas trumped Fatah in Gaza's parliamentary elections in January 2006, then US President George W Bush - who, in private conversations with Israeli and US officials, famously referred to Dahlan as "our guy" - pushed the Fatah strongman to attempt a coup, touching off a brief but bloody civil war.

But while Hamas and Dahlan have certainly had a "rocky relationship", according to the Carnegie Endowment's Sarah Yerkes, they are "united in their opposition to Abbas".

Hamas politburo deputy chairman Khalil al-Hayya last month confirmed the movement's collaboration with Dahlan, calling for the establishment of a "national rescue front" to challenge the PA amid a growing rift between the two main Palestinian factions.

"We won't stand idly by as these practices lead to deprivation of medicine," Hayya said in a statement. "This policy unites us all in Gaza and consolidates our belief that our plight is being hijacked by Mahmoud Abbas."

Weeks later, in his first public speech since taking office, newly elected Hamas leader Ismail Haniya spoke at length about his movement's warming relations with Egypt.

"We have launched a new chapter with Egypt and the relations have witnessed a big move," Haniya said, indicating that significant gaps had been closed over the past month.

For much of the past decade, Egypt has helped Israel enforce a land, sea and air blockade of the Gaza Strip, a move designed to punish Hamas after it took complete control of the territory in 2007.

Analysts say the about-turn in Hamas' relationship with Dahlan and Egypt is a direct result of measures imposed on Gaza by Abbas, aimed at pressuring Hamas to relinquish control and join a unity government.

"It's really a story of Abbas shooting himself in the foot," Nathan Thrall, the International Crisis Group's senior analyst covering Israel and Palestine, told Al Jazeera.

"If [Abbas] hadn't put this extraordinary pressure on Hamas and on Gaza by cutting salaries and then pushing for a reduction in electricity, he wouldn't have driven Hamas into Dahlan's arms."

Maybe this is a way for the Israelis to get somebody to get Hamas under control, because the PA isn't willing to do it.

Hady Amr, former US deputy special envoy for Israeli-Palestinian negotiations

The PA's demand in June that Israel cut Gaza's electricity by 40 percent left the territory's two million residents with three intermittent hours of electricity a day as summer temperatures peaked, deepening Gaza's ongoing humanitarian crisis.

A decade of siege, three sustained Israeli military offensives and an ongoing power crisis have left Gaza on the brink of "systemic collapse", according to the International Committee of the Red Cross.

Nearly 95 percent of the water pumped in Gaza is unfit for human consumption. Kitchen faucets and bathroom sinks run salty. Unemployment is at 42 percent, the highest rate in the world.

Hospitals across Gaza are operating on generators, and the UN has predicted that Gaza's fuel reserves could run out this month.

The dire humanitarian situation, coupled with Hamas' growing political isolation, has backed the movement into a corner, pushing it towards a potential partnership with a man accused of appalling crimes during his reign in Gaza.

The first step Dahlan would likely take, said Thrall, would be to distribute "blood money" - a rumoured $50m in UAE funds to be paid to the families of those killed in Gaza's 2006-2007 mini-civil war.

Meanwhile, Egypt has been at odds with Hamas since Sisi overthrew former President Mohamed Morsi in a 2013 military coup and outlawed his Freedom and Justice Party, strongly linked to the Muslim Brotherhood.

But the once-frosty relations are steadily thawing. In a guiding political document announced in May, Hamas dropped its long-time association with Muslim Brotherhood and accepted a Palestinian state along the 1967 borders in the occupied West Bank and the Gaza Strip.

Last week, in an apparent concession to Egypt, Hamas announced the creation of a buffer zone along its side of the border with Egypt, complete with watchtowers and barbed-wire fences.

Closer ties between Hamas and Egypt, backed by Dahlan and his UAE sponsors, come as a push by Cairo, Abu Dhabi, Manama and Riyadh against Qatar - a major financial contributor to Gaza - enters its second month.

Yet although Saudi Foreign Minister Adel al-Jubeir had initially included Hamas in a list of "extremist" groups supported by Qatar, the group was conspicuously absent from a formal list of demands presented to Doha around the time that Dahlan, Hamas and Egyptian officials met in Cairo in June.

"The Qatar crisis means that there's extra pressure on Hamas," Thrall said. "It feels extra isolated by Saudi, the UAE and the rest of the Arabs, and they, in turn, see an opportunity to step in and attempt to pull the group away from Iran and Doha."

Israel - which signed a 1979 peace treaty with Egypt, works closely with Cairo on security and has secretive ties with the UAE - would also look favourably at a Dahlan return.

"Israel's main goal in Gaza is containment," said Hady Amr, a former US deputy special envoy for Israeli-Palestinian negotiations. "Maybe this is a way for the Israelis to get somebody to get Hamas under control, because the PA isn't willing to do it."

Dahlan's rumoured return is a genuine cause for concern for Abbas. Twelve years into a four-year term as PA president, the 82-year-old's popularity has never been lower. A poll conducted last year by the Palestinian Centre for Policy and Survey Research in Gaza and the occupied West Bank revealed that 65 percent of Palestinians want him to resign.

Abbas was set to meet Sisi in Cairo on Monday in an attempt to head off what looks to be the inevitable return of his enemy number one - a homecoming, Amr said, facilitated by a disparate group of players pulled together under the mantra of "the enemy of my enemy, if not my friend, is my short term ally".